The aim of this study was to determine environmental pollution of water reservoirs in Osielsko region and compare the results with Regional Inspectorate for Environmental Protection reports. For this purpose the water and bottom sediment samples were collected from five lakes. Main ion concentrations and trace metal levels in waters was determined by atomic absorption spectrometry (AAS). Concentrations of trace elements in sediments were estimated for fractions <0.063 mm using the ICP-MS method. It was found that the waters are slightly alkaline with electrical conductivity up to 1,025 μS/cm. The minor and trace element concentrations were usually low. The results of research suggest a correlation between size and lake location and concentration of pollutants.